Scoring conditions were perfect and Putnam took full advantage, reeling off nine birdies with no dropped shots in a round of 63 on the Nicklaus Course at PGA West.

“The course is in perfect shape,” Putnam said. “The greens are good. I made a lot of birdies at the end. Hit a lot of close shots, a lot of 5 and 10-foot putts. I made them all, so I’ve got to be happy about that.”

Five players posted rounds of 64 to end the day one shot off the lead. Mark Wilson, Blake Adams and John Peterson posted their scores on the Nicklaus Course while Francesco Molinari shot 64 on the Arnold Palmer Course and Scott Pinckney returned the same number at La Quinta.

Defending championPatrick Reed opened with a fine 65 at La Quinta and that score was matched by his playing partner, Matt Kuchar.

In his first competitive round since the Ryder Cup, a trim-looking Phil Mickelson fired a one-under-par 71.

“My body hasn’t felt this good in years,” said the 44-year-old.

England’s Brian Davis is the best placed Brit in the field. He carded a 67 over the Nicklaus Course. Scots, Martin Laird and Russell Knox carded 68 and 69 respectively while Paul Casey scored 70 and Luke Donald struggled to a 75.

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